1. Field of the Invention
The present invention relates to a display panel and, more particularly, to a display panel capable of effectively preventing the light-leakage near the border thereof, which is resulted from the long-term exposure to the heat produced by the underlying backlight module.
2. Description of Related Art
A polarizer in a display panel can adjust and control the polarization direction of light therethrough, in order to thereby cooperate with the liquid crystal molecules for controlling of operation of the display units (pixels) of the display panel. FIG. 1A is a schematic view of a convention polarizer applied to a display panel. As shown in FIG. 1A, the polarizer 1 has a body formed by a polyvinyl alcohol (PVA) 11, and two protection layers 121, 122 locating on the top side and the bottom side of the body. The polarizer 1 is adhered to a surface of the glass substrate 14 by a pressure-sensitive adhesive (PSA) 13.
After a long-term operation of the display panel with the polarizer 1, i.e. the display panel is long-term heated by the heat produced by the backlight module, the temperature of the display panel is increased, resulting in the deformed is near the borders of the display panel, which the cause of deformed is from the shrinkage stress of the polarizer 1 is changed, for with the different thermal expansion coefficients of the body of the polarizer 11 and the protection layers 121, 122. Besides, the stickiness of the pressure-sensitive adhesive (PSA) 13 is also gradually reduced due to the heating. In general, the change of the shrinkage stress of the polarizer 1 is increased as the temperature is increased.
After the display panel has been used over a long period, the lower polarizer closer to the backlight module has the temperature higher than that of the upper polarizer far away from the backlight module, and which causes the shrinkage stress of the upper polarizer different from that of and the lower polarizer. Accordingly, the deformed near the borders of the display panel occurs, as shown in FIG. 1B. As a result, the light-leakage near the border of the display panel is experienced. In addition, the central portion of the display panel will be easily contacted with the optical films of the underlying backlight module 16 so as to cause defects of the optical films (such as backlight diffusers). Therefore, after a long-term operation, the display panel 15 of the prior art has a poor display quality due to the light-leakage near the border of the display panel and the defects formed on the optical films of the underlying backlight module.
Accordingly, it is desirable to provide a display panel with an improved display panel to mitigate and/or obviate the aforementioned problems and thereby to improve the display quality of the display panel.